Evaluation of FSO link throughput in Qatar

Abstract

Despite the vibrant advantages of Free Space Optics (FSO) technology and the variety of its applications, its widespread adoption has been hampered by rather disappointing link reliability for long-range links due to atmospheric turbulence-induced fading and sensitivity to detrimental climate conditions. A major challenge of such hybrid systems is to provide a strong backup system with soft-switching capabilities when the FSO link becomes down. The specific objective of this work is to study for the first time in Qatar and the Gulf Cooperation Council (GCC) the link capacity, link availability, and link outage of an FSO system with Radio Frequency (RF) back up (i.e. hybrid FSO/RF). In order to analyze the two transport media, we have designed a network sniffer application in Linux and embedded it in FPGA. We have installed new FSO/RF terminals and configure and align them successively. In the reporting period, we carry out measurements and relate them to real-Time weather conditions. The relative humidity, which is due to high temperature and does not generally form fogs, was found to be the main factor degrading the FSO link throughput rather than the fog as reported in previous studies in Europe and North America.